Effect of Temperature and MgCl₂ Concentration on the Catalytic Pyrolysis of Malt Waste Using Response Surface Methodology

Abstract

In the search of new energy sources, this work aimed to investigate the pyrolysis of malt waste, the major by‐product generated from the brewing industry, to produce biochar and bio‐oil. The study also explored the effects of pyrolysis temperature and concentration of MgCl2 catalyst on the yields of bio‐oil, biochar and pyrolytic gas. The pyrolysis products were analyzed using Fourier transform infrared spectroscopy. The effects of the studied variables on the yields and quality of the pyrolysis products were quantified using regression technique. It was found that the use of MgCl2 favored dehydration reactions and generated biochar and bio‐oil with less oxygen and greater calorific value, thus improving their use as a fuel. In addition, the MgCl2 accelerated the formation of intermediate compounds at low temperatures, changed the reaction pathways and decreased the reaction complexity, consequently reducing the activation energy value and the order of reactions.